Content → Hardware → GCA

• The GCA Family

With the avaiable high power bridges, it was obvious to start doing something with it.
This booster will put all previous boosters from GCA in the background.
It is very small, only 70 x 60 x 50 mm, and can be used from 1 to Z scale.
The base of this booster is an IBT-2 bridge unit.
This unit has a maximum power option to 42 Amp, but this booster is designed not to handle more than 25 Amp.
Short circuit shut off is handled on-board and maximum current is selectable by dip switch. (See below)
On top of IBT-2 unit a board is situated that has all the necessary equipment for booster function.
This board contains two small processors and various opto-couplers for isolated input and output.
Booster also has so-called cut-out for use with Railcom
Processor IC1 is controlling the output pulses, and will switch off when pulses are incorrect or not available.
Processor IC1 also handles the cut-out for Railcom.
Processor IC5 handles the maximum seelcted current.
When the output exceeds the selected value, booster is shut off, and will try to start again every second.
Inputs for LocoNet Railsync, DCC232 (direct drive inside Rocrail) and CDE (lenz).
Also any central station can be used to drive this booster.
Power for this booster should be a DC output power supply, and the maximum Amp output of this power supply should be
ALWAYS slightly more than the selected Amp on booster.
The long run test prooves that it is absolutely necessary to use a small fan for cooling , when the booster does more than 10 Amps.
So a small fan was added, which kept it below 40°C.
But on the maximum load of 25 Amp, a larger fan is undoubtly needed.
Also, the position of the unit, where air can freely stream in upside direction through the cooling grid is essential.

• Useable for Railcom
• Easy selectable maximum output current.
• Input for Railsync (LocNet)
• Input for DCC232 (inside Rocrail, no central station needed.
• With extra adapter also useable for DCC232 via USB.
• Input for CDE (Lenz)
• Only extra cooling needed, if contineous output is more that 16 Amp.(Can be done by small 40x40 mm fan,)
• All signal inputs are isolated.
• Absolute maximum power input 24Vdc.
• also available without Railcom.(with addional firmware in IC1)
• also available for DDX with Motorola/DCC mixed signals (with addional firmware).
• opto_isolated output for short_circuit indication.

The ORD-VC-12 board is mounted on top of IBT-2.
The 1st edition of this board need a smaal wire to +V of the IBT-2, for supply.
In the second edition, this is changed.
The elco located besides the screw terminals on IBT-2, needs to be removed, to make place for two header pins.
C1 on ORD-VC-1 board is connected to these pins, replacing the removed elco.
On ORD-VC-1 board a 2-pin female header is used two connect together.

The kits will have molunting supports, which need to be used in the way as shown here

The choice of power supply depends of the used scale.

Since this unit can handle a large current , it is necessary to select the maximum current output.
For example: If you use a power supply of 18V 4 Amp, the selection should be maximum 3 Amp on the booster.
When power supply can not handle the maximum selected current, the booster will not be able to shut off when a short
circuit occured.
This can cause much damage to your materials, and maybe fire hazard.
A special remark is to be stated for current versus wires, both between Booster and rails and also between booster and power supply.
Do NEVER use wire that cannot handle the selected maximum current.
A global indication:

It might be a bit overdone, but if the need for multiple boosters is there, be sure not to mix different type of boosters with ORD-VC-1.
Only combination of multiple ORD-VC-1 booster is possible.

L1 just shows that 5 Volt power is available.
L2 is On when booster is in normal function.
L2 flashes fast (8 /sec) when short circuit is found (booster is off).
L2 flashes slower (3/sec) when no pulses are coming in.

This booster needs a digital signal (DCC or Motorola) from any central unit.
These can be connected in different ways.

This connector is mainl;y used for LocoNet
Thje signals in LocoNet (called Railsync) are connected to Pin 1 and 6.\]\

Here a signal directly from Rocrail can be used
In Rocrail this can be the internal command station DDX or DCC232.
Used pin in the SUB-D9 connector are pin 3&5.

Rail connections from any digital central unit can be connected to PIN C & D
Here also a galvanic free output is available which will indicate a short circuit situation.
These pins E and GND can be connected to any input port, for your own convenience.
It is not much used, the booster controls its own short circuit protections,
but if you like it could be used to report back to the controlling pc program, that booster is off.